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arXiv · 2305.04029

Excitonic Resonances in Coherent Anti-Stokes Raman Scattering from Single Wall Carbon Nanotubes

Georgy Gordeev·Lucas Lafeta·Benjamin Scott Flavel·Ado Jorio·Leandro M. Malard
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Abstract

In this work we investigate the role of exciton resonances in coherent anti-Stokes Raman scattering (er-CARS) in single walled carbon nanotubes (SWCNTs). We drive the nanotube system in simultaneous phonon and excitonic resonances, where we observe a superior enhancement by orders of magnitude exceeding non-resonant cases. We investigated the resonant effects in five $(n,m)$ chiralities and find that the er-CARS intensity varies drastically between different nanotube species. The experimental results are compared with a perturbation theory model. Finally, we show that such giant resonant non-linear signals enable rapid mapping and local heating of individualized CNTs, suggesting easy tracking of CNTs for future nanotoxology studies and therapeutic application in biological tissues.

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Georgy Gordeev, Lucas Lafeta, Benjamin Scott Flavel, Ado Jorio, Leandro M. Malard. 2023-05-06. Excitonic Resonances in Coherent Anti-Stokes Raman Scattering from Single Wall Carbon Nanotubes. https://doi.org/10.1021/acs.jpcc.3c05696

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